Means and method of refining ore



Jan. 19, 1932. B. ANDREWS I 1,841,697

MEANS AND METHOD REFINING ORE Filed Dec. 13, 1929 gwmntoz a 2Q WWJA'WGlldrdm'w liar? (in er/1 8Aecu2m s51, I alike-m Patented Jan. 19, 193.2

were .srn'rss PAT QF -r I BENJAMIN :ANDREWS, DECEASED, -LAT-E OFHOUSTON, TEXAS, BY GUARDIAN TRUST I COIvIIEANY,.EXEGUTOE-, F HOUSTON,TEXAS S AN D -ME'IH OD 0 F REFINING ORE Application filed "December 13;1929. Serial "No/413,947.

Thisinvention rel-atesto meansandmetho d for refining by heat treatmentores such as that ofsulphur.

In various localities of the United States andelsewhere depositsofsulphur exist on the surface ofthe ground or in subterranean dryformation where it is not 'possilole'tO employ the Well known Fraschprocess o'fmining sulphur.

found in heterogeneous mixtures ofinorganic matter consistingprincipally of gypsum. Sulphur isa solid at temperature below 289 Fahr.but above that temperature it melts and-takes the formof a-slightlyviscous lfluid. It isg th ereiore,possible byheating sulphurbearing rocklike or'estoa temperature above 239 Fahr. to melt the sulphur-andseparate it from-the rock and other foreign substances. The method nowemployed ffor'winningsul- "phur fromlthese surfacebe ds is to dig-outthe ore by hand or machinery, after-which the ore'or mixture must betreated.

The most e'fiective system o f tnea'tment is by melting the sulphur outof the dross by means ofsteam or hot water, but as the melting point 0fsulphur is approximately 239 F-ahrJthe Water or steam-hasto bekept undera pressure'exceeding the vaportension at that 1::- temperature which is"approximately "2" pounds per square inch absolute;

In practice the plan generally employed is to loadthe-ore into carsWhich-are run into a la-rge cylinder, retort or giganticautoclave suchas is used for creosoting timber. The

auto-olave is sealed by boltingonto the ends removable heads ordoors.The au'to-clave is then filled with hot water which entirely envelopsthe ore and the cars. The water is then further heated *by injectingli've steam directly into the autoclave or means of steam in closedcoils. The auto-cla've and contents-are thus raised to the desired tem-*perature. Usually a steam pressure of 100 lbs. is used which brings theinternal temperature oi the auto-clave to about 340 Fahr. Such anoperation obviously cannot be carried out -'continuously, but theautoclave must be charged and discharged treating the "ore in batches.Much time and lab or Sulphur as it usually occurs in nature is isrequired to closean'd seal the auto-clave; further time is 'requir'ed'to raise the temperature of the autoclave to the necessarytemperature.After thesulphur is melted outof theore much time is required 'to cooldown the autoclave and contents so that the doors may be opened. Takingall in all the operation is extremely slow and tedious "to; say nothinga of being wastetulin heat units.

It is the object ofthe invention to provide i a means and apparatus fortreat-ing'the sulphur in an autoclave whereby the raw ore maybesu'bjected to the heattreatment and the sulphur removed and'theremaining slag withdrawn "from the Water in a continuous operation andwherein the desired pressure upon the water in contact with the sulphurore is maintain'ed'by means ofthe forc'e of gravity, thus making itpossible 'to introduce and remove the'ore from the autoclave without theuse of a cumbersome door'system and its contingent tedious, slow andexpensive operation.

Other and further objects of the invention involving the feeding oftheraw oreydrlmping of the slag from the conveyors and the maintenance ofthe entire apparatus willbe readily apparent'ito those-skilled in theart.

It is obvious that 'the improved means and method may take variousforms. However, for purposes of illustration, it is showndiagrammatically herewith only in one form for conveying the ore to andfrom the treating apparatus. It isnot desired to be limited to thisparticular form, but it ismerely illustrated for the purposes ofdescription. Neither is it desired to limit the use of the invention tothe production of sulphur, but it may be used for many purposes where itis desired'to treat by continuous processmateria'l which requiressubmersion in liquidsor their vapors raised to temperatures whichindicate vapor tensions higher than normal atmospheric pressure. I

Fig. 1 i'sa diagrammatic elevation and layout of such apparatus as maybeutilized in connection with the improved method and shows an endlesstrain of buckets passing through "a double inverted tube siphon'containing water heated above the melting temperature of sulphur.

Fig. 2 is a sectional view taken through the tube and showing one formof track construction which may be used to support the corn veyor.

The buckets are filled at A, pass through the siphon B where the sulphuris melted and separated, and are finally dumped of their depleted gangueat C.

It will be noted that the tube 2 as shown consists of a double invertedsiphon. With this structure it is possible to maintain the desiredtemperature in the central portion 8 by taking advantage of naturesphysical phenomena, as here described.

Inasmuch as the density of water above 40 Fahr. decreases materiallywith temperature, as soon as water is heated it immediately tends toflow to the highest point possible.

Inasmuch as water is an extremely poor heat conductor heat applied towater has no effect whatever of heating the water below the level atwhich the heat is applied.

Referring to the drawings, it is the intention to introduce the steam orhot water adjacent to 2"; this will cause the heated water to rise andall of the water inside of the tube above that level in time will beheated uniformly by convection, but as stated above, no water below 2727 will be heated. The temperature of the water may be raised to anydegree desired providing a vapor ten sion is not reached suflicient toform steam in the upper space at 8 and thus force the hot water downbelow the lowest point of the siphon at 5 and allow the hot water toescape into the legs 4.

In the operationof the apparatus hot water may be introduced into thelegs 4-4. intentionally either by increasing abnormally the temperaturein 8 or by forcing a surplus of hot water into 8 and thus displacing itscontents into the legs of the tube, or by injecting steam or hot waterdirectly therein. It will be understood, however, that under nocircumstances can the temperature in the legs of the tube xceed that ofboiling water, because the top is open to the atmosphere.

It is desirable to have the legs of the apparatus as hot as possible sothat the material may be pro-heated before entering the melting chamber8. Under some circumstances, for heat economy sake, it will be found anadvantage to run the apparatus in one direction for awhile and thenreverse the operation and run it in the other. It may als be foundexpedient to use two siphons in series, the second one providing meansfor dumping the buckets under temperature sufficient to keep the sulphurmelted; as the small amounts of waste sulphur still adhering to thegangue under some conditions if cold and solidified will be suiiicientto cause trouble in dumping by sticking to the sides of the bucket.

The method contemplates arranging a tube in the form of a doubleinverted siphon such as indicated at 2 in Fig. 1. This tube will haveconsiderable length but may be arranged in any desired form, preferablyor approximately shaped like an elongated W shown in Fig. 1. It may berectangular in cross section as shown in Fig. 2, or round if so desired.The tube, however, will be arranged in such a manner so as to be filledwith water. The wings of the W indicated at f will have a considerableelevation, so that the vertical distance from the point indicated at 5to that indicated at 6 or 6 will be sutlicient to maintain the desiredliquid heat or pressure upon the central or heat treating portion shownat 8. It is readily apparent that when the tube is filled with waterthat the gravitational pressure of the water from 5 to 6 will be exertedupon the portion at 8. In this manner, if it is desired to maintain apressure of say 100 lbs. per sq. inch on the portion at 8, it will benecessary to have an elevation difference between 8 and 6 of at least240 feet.

The tube when fully constructed will therefore occupy a considerablearea and ma 1 be arranged upon a hillside or in a smal valley or otherdepression in the earth; it may be constructed as a tunnel, or, ifdesired, a suitable derrick-like supporting structure may be arranged.

A boiler is shown indicated generally at 10 and having inlet pipes 11and 12 leading into the tube. These pipes may open directly into thetube so that the heated fluid, water or steam, may flow into the tube,but if desired these pipes may encircle the tube or be placed within itand merely convey the heat of the steam in the pipe to the contents ofthe tube by conduction and not by direct fiow. The inventor has shownpipes at 13 and 14 as a means of completing the circulation of the fluidthrough the boiler 10. Such a plan may be advisable where there is adearth of water as is the case where some of the sulphur deposits exist.This layout, however, is optional, and other forms may be used ifdesired.

In order to convey the ore into the tube an endless track conveyorhaving a plurality of buckets thereon used. It is obvious, however, thatan endless belt or train of cars or any other type of conveyor may beused without departing from the spirit of my invention. A hopper shownat having a suitable valve 21 is shown diagrammatically in Fig. 1 as ameans of feeding the ore into the buckets. From this point the bucketspass over any suitable guide means at 22 and enter the tube at the point6.

By referring to Fig. 2 it will be seen that the buckets have perforationsuch at 25 therein and thus permit the molten sulphur to drop CJI .. forcooling. After the buckets pass out of the central portion 8 and intothe left hand wing at at a considerable amount of heat which theycontain will be transferred to the water in this wingof the tube, thusto a considerable extent some of the heat units are not dissipated asthey are absorbed by the water from the heated buckets. After thebuckets pass around the guide members 22 or 22' they are engaged by adischarging apparatus shown at which may consist in any desired form ofmechanism which will rotate the bucketupon its pivot pin in order todischarge the slag and other foreign material which remains therein. Itwill be seen that the buckets assume an upright position due to gravityand are then adapted to receive another charge of ore from the hopper20. Fig. 2- also shows suitable tracks such as 30 upon which wheels 31are adapted to travel. In this manner buckets will progress smoothlythrough the tube and the motive power may be applied to the rollers asat 22 to propel the endless conveyor.

From the foregoing it will be apparent that the inventor was enabled torefine the sulphur by a continuous operation and to avoid the use of asealed container and the contingent loss of heat units he was notrequired to maintain a pressure by mechanical means. This is a materialadvance in the art over the means and method now generally in use.

Having thus described the invention, what is claimed is:

1. In the'treatment of materials under heat and pressure in anautoclave, theprocess of providing free lngress to and egress from saidautoclave, comprising providing openings to said autoclave andmaintaining a gradually increasing pressure from said openings by aliquid static head to the central portion of the autoclave.

2. A method of subjecting materials to a hydrostatic pressure treatmentin a continuous process, including passing the material through anautoclave wherein the pressure is maintained by a gravity head.

3. A method of providing a continuous cycle of hydrostatic heat andpressure treatment for materials, including passing the material througha heat and pressure area, wherein the pressure is maintained by agravity head.

at. A method of subjecting materials to a heat and pressure treatmentincluding pass ing the material through a heated body of liquid, whereina portion of the liquid is under the hydrostatic pressure of theremainder thereof.

' 5. In a pr'ocess of refining material the steps :of passing thematerial continuously through an :open ended container where it issubjected to heat and pressure, the pressure in the container being thatof-the hydrostatic head of the liquid in the-container.

f6. A method oftrea'ting sulphur ore having foreign substances therein,including arranging awater columnto obtain'apressure which will preventvaporization thereof at the melting temperature of sulphur, passing theloose sulphur ore through the water col- 'umn to melt the sulphur, andwithdrawing the refined sulphur and the foreign subh staneesseparatelyfrom the water column. 7

7. A method-of refining sulphur including passing orethrough a column-ofwater heated to at least the melting temperature of sulphur; andmaintaining a gravity pressure on the heated water suflicient to preventvaporization. I

8. A device for refining sulphur including a tube having the endsthereof and the center elevated, a conveyor arranged to pass sulphur orethrough said tube, means to maintain heated liquid in the center of saidtube whereby the sulphur is melted from the ore.

9. A sulphur treating apparatus including in combination an irregularenclosed passage open at both ends, said ends being at an elevationabove the remainder ofsaid passage, a central portion of said passageelevated above the part intermediate said ends whereby fluid placed insaid passage will exert a V gravity pressure in said central portion,means to convey ore through said passage, and means to maintain saidcentral portion heated to at least the melting temperature of sulphur.

10. A device for melting sulphur includ- 1'05' ing apassage adapted tobe filled with water, means to heat a portion of the'water to themelting temperature of sulphur, said passage being arranged so thatgravity pressure of the water in the central portion of "1-10 saidpassage will prevent vaporization of the water at the meltingtemperature of sulphur.

11. An ore refining apparatus including in combination an ore conveyingmechanism, a tube through which said mechanism is adapt- 1 15 ed topass, said tube being characterized by the fact that when filled withwater a static pressure at least sufficient to prevent vaporization ofwater at 239 F. will be exerted upon a portion of said tube, means toheat 120 said portion and mean to draw off the melted I sulphur.

12. A method of treating ope by a continuous cycle of operationincluding feeding the raw ore into a body of liquid in an open I25receptacle, conveying the ore to a point in the receptacle where thehydrostatic head is greater than the vapor tension of the liquid andpassing the slag from the liquid and I receptacle.

13. The process of treating ore by subjecting it to temperature andpressure in eluding passing the ore in acycle through a body of liquidunder the required pressure due to its own hydrostatic head.

14. The process of treating ore by subject ing it to heat and pressureincluding pass ing the ore in a cycle thru a body of liquid maintainedat a temperature and pressure exceeding that at which it would normallyvaporize.

In testimony whereof, I hereunto afllx my signature this the 6th day ofDecember, A. D. 1929.

VALTER BROW NE BAKER, Vice President of Guardian Trust 00., Emacutor ofBenjamin Andrews, Deceased.

